The Freedom SW Inverter/Charger is offered with the GFCI (Ground Fault Circuit Interrupter) option to enable you to plug electronics directly on the inverter/charger. This ground fault protected AC output is also a requirement for certain mobile applications. The GFCI plate can be mounted directly and quickly on the Freedom SW Inverter/Charger. This optional accessory is compatible with both old and new generation Freedom SW products.